*********************************************************************
*** Fit treated unit on lags to find best fit  
*** Forward shift only
cd /disk/agedisk3/medicare.work/poterba-DUA52260/jetson-dua52260/botox/synth/100pct/robustness/forwardonly
use /disk/agedisk3/medicare.work/poterba-DUA52260/jetson-dua52260/botox/synth/100pct/growthgroupspanel.dta, clear 

levelsof group, local(levels)
keep group dt pmt_amt 

reshape wide pmt_amt, i(dt) j(group)
tsset dt 

matrix distanceLag = (0,0,0)
* No leads
* 3 columns: group, lag period, distance

set matsize 11000


*** Only want to keep botox pre-period
local treatment_period = mofd(mdy(6,5,2007))
replace pmt_amt999 = . if dt >= `treatment_period'

** Find max lag so that there are 3 years of pre-period data 
summarize dt 
local maxlag = `treatment_period' - r(min) - 36
	** Treatment period - min  = length of end window 


gen diff = 0 
*** Regress, storing leads and lags
foreach g of local levels {
	disp `g'
	* Skip Treated group
	if `g' == 999{
			continue
		}
	foreach t of numlist 0/`maxlag'{
		*disp `t'
		qui replace diff = (pmt_amt999 - L`t'.pmt_amt`g')^2
		qui summarize diff 
		matrix distanceLag = (distanceLag \ `g', `t', r(sum)/r(N))
		}

}

svmat distanceLag
keep distanceLag*

rename distanceLag1 laggroup
rename distanceLag2 lagperiod
rename distanceLag3 lagdistance

drop if laggroup == 0
save distancelag.dta, replace

********************************************************************************
*** Find best fit per group
cd /disk/agedisk3/medicare.work/poterba-DUA52260/jetson-dua52260/botox/synth/100pct/robustness/forwardonly
use distancelag.dta, clear

* Create best fit per group
keep laggroup lagperiod lagdistance
drop if mi(laggroup)
bysort laggroup: egen minlagdistance = min(lagdistance)
keep if lagdistance == minlagdistance
drop minlagdistance

* Prep for merge 
rename laggroup group
rename lagdistance mindistance
replace lagperiod = -1*lagperiod
rename lagperiod period 
save groupleadlags.dta, replace